public function testGettersAndSetters()
{
$clause = new ValuesClause();
$field = new StringExpression();
$field->setValue('abc');
$null = new ValueExpression();
$this->assertFalse($clause->hasExpressions());
$clause->addExpression($field);
$this->assertTrue($clause->hasExpressions());
$this->assertSame([$field], $clause->getExpressions());
$clause->clearExpressions();
$clause->setExpressions([$field, $null]);
$this->assertTrue($clause->hasExpressions());
$clause->clearExpressions();
$this->assertFalse($clause->hasExpressions());
$this->setExpectedException("InvalidArgumentException");
$clause->setExpressions([$field, $null, 'abc']);
}
